Why Shrinkage Matters to Buyers in Russia
Shrinkage in aluminum die casting isn’t just a technical issue—it’s a quality, cost, and delivery risk for any buyer. In Russia’s industrial sectors, especially heavy equipment, energy, and defense-related machinery, even small internal voids or surface dents can result in part rejection or machinery failure. Over the past 20+ years, we’ve seen how Russian buyers prioritize stability and tolerance in parts like housings, valve bodies, and brackets. That’s why understanding how to avoid shrinkage is essential from a buyer’s point of view—not just for foundry engineers.
What Is Shrinkage in Aluminum Die Casting?
Shrinkage occurs when the molten aluminum alloy cools and solidifies, leading to volume reduction and internal cavities or surface marks. Most common in thicker sections, junctions, and low-pressure areas, shrinkage shows up as:
- Internal porosity
- Surface sink marks
- Cracks at junctions
- Dimensional instability
From our real-world projects, we’ve found that even in ADC12, one of the most popular die casting alloys, shrinkage-related issues can appear if gating, venting, and cooling aren’t handled precisely.
Key Causes of Shrinkage in Russian-Targeted Castings
In many Russian orders, parts have heavier wall thicknesses and high thermal load applications. This makes certain factors more critical:
| Cause | Impact in Russian Projects |
|---|---|
| Non-uniform wall thickness | Leads to internal voids in thick sections |
| Inadequate feeding | Starves material during solidification |
| Incorrect gating system | Causes premature cooling before full cavity fill |
| Poor mold temperature control | Creates inconsistent microstructure |
| Overheating or underheating the alloy | Changes viscosity and shrinkage potential |
In our own experience, uneven solidification rates in heavy wall housings (over 6mm thick) are a top trigger in Russian machinery castings.
Practical Methods We Use to Avoid Shrinkage
Here’s what we do in our factory to keep aluminum die cast parts shrinkage-free—especially when working with demanding buyers from Russia.
1. Smart Mold Design with Uniform Wall Thickness
We always aim to keep wall thicknesses between 2.5 mm and 4.5 mm. In areas where a heavier section is unavoidable, we incorporate fillets or ribs to guide cooling evenly.
2. Overflow and Vent Placement
For Russian orders, especially large enclosures or motor housings, we design overflow cavities and deep vents to let gases escape and ensure pressure remains consistent.
3. Alloy Selection and Temperature Control
We mostly use ADC12, but we strictly control the pouring temperature between 640°C and 680°C. Too high, and it traps air; too low, and it doesn’t flow well. This fine-tuning matters more when the part size is over 1 kg.
4. Mold Temperature Monitoring
Our die temperatures are kept between 180°C and 250°C. We use mold temperature controllers with ±5°C accuracy, especially for parts shipped to colder regions like Siberia or Ural—where metal performance needs to stay stable.
5. Vacuum Die Casting (for Specific Parts)
In projects where zero porosity is required—like pump housings or control box covers—we use vacuum-assisted die casting. While this costs more, it avoids 95% of shrinkage issues.
Russian Buyer Case: Large Housing with Internal Porosity Issue
One client from Yekaterinburg initially ordered a series of large aluminum control housings from a local supplier. After delivery, 18% of parts failed X-ray inspection due to deep shrinkage cavities. Their engineering team assumed this was a material problem—but the real issue was improper gating and lack of controlled cooling.
We took over the project. By redesigning the part for uniform solidification, adjusting the die cavity with additional overflows, and using a modified ADC12 with stricter silicon limits (10.5% ± 0.3%), we brought their part defect rate down to less than 1.5%. That same customer still works with us now, placing annual bulk orders.
How to Avoid Shrinkage Issues in Your Next Order
If you’re sourcing aluminum die castings for use in Russia or export projects involving Russian industries, here are our top buyer-side recommendations:
- Ask for the solidification simulation report before production (if your part is over 500g).
- Specify your porosity standard clearly—e.g. ASTM E505, Grade C or better.
- Don’t skip X-ray or dye-penetration tests for critical pressure or thermal parts.
- Request a wall thickness consistency review during DFM stage.
- Avoid over-polishing parts if they need post-machining—removal of metal may expose shrink voids.
How Our Factory Handles Russian Projects Differently
We understand the specific climate, application, and transportation conditions involved in parts used across Russia. That’s why:
- We use wooden or steel-reinforced crates for packing heavy castings.
- We apply anti-corrosion coatings for parts bound for coastal or cold regions.
- We maintain documentation in both English and bilingual Russian-English if requested.
- We conduct process FMEA for orders over 10,000 pcs/year to prevent recurring shrinkage defects.
Avoiding Shrinkage Isn’t About Luck—It’s About Process
If you’re sourcing aluminum castings for the Russian market, shrinkage is one of the first silent killers of product reliability. We’ve spent over two decades refining our processes to keep that risk close to zero—not by chance, but by precision and control. Choosing a supplier who understands how to prevent these issues from the ground up saves time, budget, and trust.
